IMG Stageline DSP in REW

[Heimkinoberatung]

Hi all,

does anybody know if the DSP Processors from IMG Stageline are somehow reproduceable in REW? They are based on ALLDSP modules.

If not, what would be the approach to find out how an unknow DSP can be re-produced with the generic EQ?

 

[dcibel]

Build some filters, measure through loop-back and compare.

 

[ddude003]

Can you please be more specific about which device by IMG Stageline and/or ALLDSP you are asking about? And are you wanting to create EQ and/or Crossover filters for that device with REW? You could compare what types of filters the device has (read the operators manual) verses what is available in the Generic Extended EQ selection which is new in REW https://www.avnirvana.com/threads/v5-20-14-early-access-build.11154/...

 

[Heimkinoberatung]

I have the IMG DSP-26 , which is a little bit older model and want to created EQs. I did some electrical measurements today and compared how REW generic EQ (V 5.20.3) behaves against the IMG. Q factors have to be doubled on the IMG to match with REW. Crossovers seem to match fine.
So you mean to say in the new build there´s a way to build kind of customized EQs in the extended version to match against any real DSP?

 

[ddude003]

I am saying that you can click the link provided above, read down about a page where there is a description of the Generic Extended EQ...

This!!! >>> "There is a new "Extended" generic equaliser option with 20 filters which can each support a range of high order types including low pass, high pass and shelf filters with slopes up to 48 dB/octave" <<<

Then at the top of that linked page there are links to the latest and greatest version or REW that includes those new features... Try it!!!

 

[John Mulcahy]

The 5.20.14 build has an option for a Generic configurable EQ which lets you set the number of filters, parameter ranges and choose from a few different Q/BW definitions.

 

[Flo94]

Hello,
I apologize for reopening a previous discussion, but I am experiencing an identical problem to the original poster.
I am using a Vibe Audio POWERBOX65.4-8MDSP-V3 in my vehicle and have observed discrepancies between the measured frequency response after applying REW autoEQ filters and the predicted response.
Through experimentation, I have determined that the Q factors implemented in my DSP are symmetric and necessitate doubling the values recommended by REW to achieve a response curve consistent with REW's predictions.
As an illustration, if REW recommends a filter at 1kHz with a -3dB gain and a Q factor of 2, I must configure my DSP with a filter at 1kHz, -3dB gain, and a Q factor of 4.
I would like to inquire whether this behavior indicates a defect in the DSP's implementation or if there exist alternative definitions of Q factors beyond those currently supported by REW?

 

[John Mulcahy]

There are a few relatively standard formulations for Q, here's Andy's take on that. The IMG choice seems unusual, haven't come across another equaliser like that, but at least the conversion is pretty simple when it comes to entering values.

 

[Flo94]

Thank you for your help. I've tried contacting Vibe Audio support, but they haven't responded.